Not to worry, we've got 421 and 9248. Let's get to adding them!

Step 1: We'll start by adding the digits 1 & 8 in column 1 and get 9.

Step 2: We'll start by adding the digits 2 & 4 in column 2 and get 6.

Step 3: We'll start by adding the digits 4 & 2 in column 3 and get 6.

Step 4: We'll start by adding the digits 0 & 9 in column 4 and get 9.

So, 421 + 9248 = 9669.

